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DFT study on the cycloreversion of thietane radical cations
Luis R Domingo1, Raúl Pérez-Ruiz, Juan E Argüello
1Departamento de Química Orgánica, Universidad de Valencia, Dr. Moliner 50, E-46100 Burjassot, Valencia, Spain. domingo@utopia.uv.es
The Journal of Physical Chemistry. A
|May 13, 2011
Summary
The cycloreversion of thietane radical cations proceeds through a stepwise mechanism. Different pathways yield alkenes, thiobenzophenone, or formal [4+2] cycloadducts depending on the specific thietane derivative.
Area of Science:
- Computational Chemistry
- Organic Chemistry
- Reaction Mechanisms
Background:
- Thietane radical cations are reactive intermediates.
- Understanding their cycloreversion (CR) mechanism is crucial for synthetic applications.
Purpose of the Study:
- To elucidate the detailed molecular mechanism of thietane radical cation cycloreversion.
- To identify the factors influencing the reaction pathways and products.
Main Methods:
- Density Functional Theory (DFT) calculations.
- Utilized the UB3LYP/6-31G* level of theory.
- Analyzed reaction pathways, intermediates, and transition states.
Main Results:
- The CR process follows a stepwise mechanism initiated by C2-C3 bond breaking.
- Two distinct pathways were identified: one forming ion-molecule complexes and another forming radical cations.
- Specific thietane derivatives (1a and 1b) exhibit different preferences for these pathways, leading to varied products like alkenes, thiobenzophenone, and formal [4+2] cycloadducts.
Conclusions:
- The study provides a detailed mechanistic understanding of thietane radical cation cycloreversion.
- The findings highlight the influence of substituent effects on the reaction pathway and product distribution.
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